Presentation on theme: "Research on the Speciation of Chromium as Relates to CCA."— Presentation transcript:
Research on the Speciation of Chromium as Relates to CCA
Research Project: Assessing the Impact of Chromium in the Environment Assessing the Impact of Chromium in the Environment Funding provided by the Florida Department of Environmental Protection RCRA Program
Master of Engineering Thesis Topic: Chromium Speciation in Environmental Media Impacted by the Wood Preservative Chromated Copper Arsenate Mr. Jin-Kun Song
Chromium Exists as Several Chemical Species Most common oxidation states: 0, +3, +6 0: Elemental Chromium (Cr) +3: Trivalent Chromium Species: Cr +3, Cr 2 O 3 +6: Hexavalent Chromium Species: CrO 4 2-, Cr 2 O 7 -
Chromium Speciation Important! The characteristics and properties of trivalent chromium and hexavalent chromium are greatly different. Cr(VI) is much more toxic and mobile than Cr(III)
Difference between Cr(VI) and Cr(III) Factored into Regulations RCRA Regulations 40 CFR 261.4(b)(6)(i) A solid waste that is a characteristic or listed hazardous waste solely because of chromium is not hazardous if…..
(A) The chromium in the waste is exclusively (or nearly exclusively) trivalent chromium; and (B) The waste is generated from an industrial process which uses trivalent chromium exclusively (or nearly exclusively) and the process does not generate hexavalent chromium; and (C) The waste is typically and frequently man-aged in non-oxidizing environments.
IC System Detector Integrator Analytical Column Guard Column LC Pump
Experiment 1 Examination of the fate of hexavalent chromium in soils spiked with CCA solution Cr(VI)/Cr(total) concentrations were measured over time Leachable Cr(VI) and Cr(III) concentrations measured over time (SPLP)